Field of the Invention
The present invention relates to an image processing apparatus and a control method for the same.
Description of the Related Art
With higher magnifications of image pickup apparatuses, for example, when zooming by using a 60× optical zoom lens, there have been cases where a subject moves outside a field angle due to the hand shake of a photographer or the movement of the subject if the photographer attempts to frame the subject within the field angle. Accordingly, an image pickup apparatus including a subject tracking control function that automatically tracks the subject so as to frame the subject that is continuously moving within the field angle has been proposed.
Japanese Patent Laid-Open No. 2010-93362 discloses an image pickup apparatus that tracks the subject that is continuously moving toward the inside of the field angle (applies an optical tracking system) by driving an image shake correction mechanism for correcting an image shake. Additionally, an electronic tracking system has been known that serves as a tracking system of the subject that is different from the optical tracking system. When the electronic tracking system is applied, the image pickup apparatus tracks the subject and keeps it within the screen by dividing the inside of the screen for each block, detecting the subject from the screen by using a specific template matching such as the face of the subject, and trimming it around the detected area.
In the optical tracking system, a drive amount for performing track-driving of the subject is added, in addition to a drive amount of the shake correction mechanism for correcting the image shake (drive amount of the shake correction). Therefore, when the apparatus is designed such that the drive amount of the shake correction mechanism is made large by taking the driving amount for performing the track-driving of the subject into account, the size of the image pickup apparatus increases. Additionally, unless a drive limit of the shake correction mechanism is changed, the drive amount of the shake correction reduces by the drive amount for performing the track-driving. Additionally, when the drive amount of the shake correction mechanism becomes too large, the linear range of a sensor (for example, a Hall sensor) that detects the position of the shake correction mechanism is exceeded, the position is detected in the range of non-linear element, and thus, the performance of the shake correction mechanism decreases. Additionally, in the case of applying the electronic tracking system, if the subject moves outside the field angle, the image pickup apparatus cannot detect the subject, and the tracking of the subject is impossible.